Ultrasound-assisted extracted dietary fibre from culinary banana bract as matrices for anthocyanin: its preparation, characterization and storage stability.

Dietary fibre (DF) functionalized with polyphenols is a functional ingredients as it provides the health benefits associated with consumption of both DF and polyphenols. The present study endeavoured to prepare DF-anthocyanin formulation with different ratio of pigment-matrix where DF and anthocyanin were extracted from culinary banana bracts. The formulated powders were studied for its antioxidant, structural properties and fluorescent properties. DF-anthocyanin formulation exhibited enhancement in anthocyanin content with increase in antioxidant content and it was highest for DF-A3 with better color values (L*, a*, C*) compared to other formulations. The structure of the formulation was mainly attributed to the structure of DF and anthocyanin as evidenced by FT-IR. Moreover, changes in the degree of crystallinity were found after addition of anthocyanin in fibre matrix. The morphology study by SEM confirmed the entrapment of particles (1.97-3.88 µm) on the network structure and surface of DF. Additionally, Akin fluorescence emission spectra of DF-A3 with anthocyanin extract further confirmed the formation of DF-anthocyanin complex. Storage stability study showed DF-A3 with lowest degradation rate (k = 0.0002 day-1) and half-life period of 87 days.

Chemical profiling and functional properties of dietary fibre rich inner and outer bracts of culinary banana flower.

The present study endeavoured to evaluate the nutritional, phytochemical and functional properties of outer and inner bracts of culinary banana flower which is a by-product of banana production. Both outer and inner bracts were found to be rich in dietary fibre (61.13 and 66.22%, respectively) along with other chemical compositions including proximate, minerals, and antioxidant-rich phenolics both free and bound. In addition, the functional properties including glucose dialysis retardation index (GDRI) of outer and inner bracts were also studied. The outer and inner bracts exhibited total polyphenols 7.56 and 9.44 mg phenols/g dry sample, respectively. The polyphenol profile by HPLC, revealed the presence of significant amount of free and bound phenolics in both outer and inner bracts. Functional properties of these dietary fibres-rich fractions of culinary banana flower exhibited lower bulk density, higher water-holding capacity, oil-holding capacity, and water-swelling capacity in outer and inner bracts than cellulose. The outer and inner bracts showed relatively higher GDRI compared to control and cellulose. The results revealed that both the outer and inner bracts of culinary banana flower are rich source of dietary fibre along with high antioxidant activity and could be one of the promising functional ingredients for low-calorie and high-fibre food product.